Accession Number : ADA321216

Title :   Fundamental Studies in Cryogenic Cooling of Power Electronics.

Descriptive Note : Final rept. 1 Sep 95-31 Aug 96,

Corporate Author : KENTUCKY UNIV LEXINGTON DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Chow, L. C. ; Chen, X. Q. ; Sehmbey, M. S.

PDF Url : ADA321216

Report Date : SEP 1996

Pagination or Media Count : 62

Abstract : This report is divided into two studies. The first deals with the measurement and modeling of film thickness produced during spray cooling. The experiments were conducted using pressure and air atomizing nozzles. The film thickness increases with decrease in flow rate for pressure atomizing nozzles, although the decrease is small. For air atomizing nozzles, increase in flow rate causes an increase in film thickness while and increase in air velocity causes a decrease in film thickness. Models were derived for both forms of sprays. The second study deals with the effect of operating temperature and cooling technique on power MOSFET characteristics. This numerical study found that the maximum drain current can be more than quadrupled at 78 K as compared to room temperature operation. In comparing spray cooling and immersion cooling, it was found that the maximum drain current possible with spray cooling was more than double that with immersion cooling.

Descriptors :   *ELECTRONIC EQUIPMENT, *COOLING, *POWER EQUIPMENT, *CRYOGENICS, VELOCITY, THICKNESS, LOW TEMPERATURE, MODELS, AIR FLOW, NUMERICAL ANALYSIS, ROOM TEMPERATURE, DRAINAGE, LOW RATE, THICK FILMS, SPRAYS, IMMERSION, MOSFET SEMICONDUCTORS.

Subject Categories : Electrical and Electronic Equipment
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE